Surgical site marking does not affect sterility.

BACKGROUND

In 2005, surgical site marking became mandatory in Australia, with the introduction of the first Australian guidelines to prevent wrong site surgery. It has been our experience that most surgical site marking occurs with the use of a non-sterile marking pen, which has been used on multiple patients and there is little information in the published work about the effects of surgical site marking carried out in this fashion. Our aim was to determine whether the sterility of a surgical site was affected by surgical site marking with a non-sterile surgical marking pen.

METHODS

Both forearms of 20 volunteers would simulate surgical sites. Surgical site marking was carried out on right forearms with the same non-sterile surgical marking pen, whereas left forearms were unmarked controls. Microbiology swabs were taken from both forearms before, and after, skin sterilization with 10% povidone-iodine. Routine cultures were carried out on the swabs after sodium thiosulphate was used to deactivate residual iodine. Cultures were assessed for growth after 5 days.

RESULTS

One of the 20 marked forearms and 15 of the 20 unmarked forearms had bacterial growth on cultures before skin sterilization (P < 0.1). After sterilization with iodine, no bacterial growth occurred in the cultures of the swabs taken from the marked or control arms.

CONCLUSION

Surgical site marking carried out with a non-sterile surgical marking pen did not contaminate the surgical site. We recommend the practice of surgical site marking.